1. The Field of the Invention
This invention relates to towing apparatus, and, more particularly, to novel systems and methods for securing trailers to towing vehicles with hitches.
2. The Background Art
Trailers have been towed since the earliest days of the wheel. A cart or wagon towed behind an animal is a trailer. In modern times, trailers are secured to towing vehicles by a multiplicity of methods, including frame-mounted hitches and bumper-mounted hitches. Tractor-trailer rigs use fifth-wheel towing systems. Similarly, recreational vehicles sometimes use fifth-wheel towing systems or often a receiver-type mounted ball hitch.
A receiver hitch relies on a receiver cavity or tube securely mounted to the frame of a towing vehicle. The receiver is reinforced and provided with an aperture for receiving a trunnion. A trunnion, supporting a hitch, may be secured into the receiver. The hitch may be a pin, pintle, or ball type hitch, typically, but need not be limited thereto.
For recreational users, receiver-type hitches present several common problems. The more important problem may be the difficulty of attaching a greasy hitch to a vehicle and detaching the same after use. Although receiver-type hitches are generally adaptable to receive various trunnions with various types of hitches, the very nature of a receiver hitch may make it problematic. If a trunnion is not removed after use, then a person may accidentally strike a shin or knee on the extending hitch or trunnion when no towed vehicle is attached. If the hitch is removed, it is cumbersome to move, requires some immediate storage place, and may be filthy with grease. Due to the weight of the hitch and trunnion assembly, a person removing the trunnion and hitch from a receiver is likely to soil clothing.
Thus, it would be an advance in the art to provide a hitch mount that can be stowed without projecting inconveniently far from the bumper, substantially within the envelope of a vehicle, or even without extending behind the bumper on certain embodiments.
Any towed devices require one of several, common, different sizes of ball hitches. Accordingly, selective stowage and presentation of multiple sizes of ball hitches on a single mount, alone or in combination, without having to use a tool to replace the ball hitch, would be a benefit and convenience.
One may desire that the sizes and ratings of two ball hitches to be used together be different, yet that each ball hitch be adequately supported, with reasonably balanced support of loading in all portions or regions thereof (e.g. neck, ball, stud, etc.). Accordingly, it would be an advance in the art to provide a method for designing a ball hitch, or a set of ball hitches that could accommodate the load and geometric considerations that both balls will need to function at full, rated load, and all expected conditions.